This is what I have read about this. This pose is used by many many world leaders and it is a symbol of the hidden hand that shapes history. This is a good site that talks about it. http://vigilantcitizen.com/vigilantreport/the-hidden-hand-that-changed-history/
That site is anything but “good”; it appears to spout nonsensical occult theories, and despite its author claiming to have a degree in politics, much of the non-occult stuff he writes about historical political figures is flat-out wrong.
Looks like he’s playing with his nipple.
ETA: Seriously. Check out his expression.